Design of Pelletron accelerator using novel accelerating tube without gap insulators

Abstract A novel electrostatic accelerating tube, free from gap insulators, is designed that address the limitations of traditional metal-insulator bonded accelerating tubes, which are costly and prone to damage from high-voltage discharges and beam impacts. This design uses ultra-high vacuum (UHV) as the insulator, with electrodes placed in series under the vacuum. High voltage is coupled longitudinally to the first cylindrical electrode via a ceramic-bonded stainless steel flange, with homogeneous electric field flatness of 0.002 around the mid region of EAT. Electrostatic analysis using COMSOL Multiphysics and TRACK code confirms the field homogeneity and smooth beam acceleration. Designed for 75 kV operation, extendable to q × 100 keV (q is the charge state of the beam) energy gains, it leverages vacuum-compatible resistors for inter-electrode HV coupling. Field flatness is extendable to a few meters of length and thus enabling megavolts. The grounded cylindrical structure ensures safety and offers an economical, scalable design for small, low-energy implanters, Pelletron accelerators, and mass spectrometers.